The purpose of the proposed program is to thoroughly characterize the primary culture system which we have developed for the human prostate so that it can be utilized as an in vitro model system for the study of the prostate and prostatic disease. Such characterization will include the identification of biochemical and antigenic markers from tissue extracts and from prostatic fluid. It also will involve the analysis and definition of the natural history of the prostate and of primary cultures derived from the prostate. The relationship of these parameters to prostate disease also will be investigated. Prostatic fluid and tissue extracts will be fractionated by polyacrylamide and agarose electrophoresis and specific components will be identified by immunoelectrophoretic procedures. Purified fractions obtained from preparative columns will be further purified by immunoabsorption. Purified antigens will be used in the hybridoma technique for monoclonal antibody production. A combination of phase contrast microscopy and photography, time-lapse cinematography, scanning and transmission electron microscopy, histo- and cytochemistry and immunochemistry will be used to characterize primary cultures.